CVE-2026-23099 bonding: limit BOND_MODE_8023AD to Ethernet devices

What is CVE-2026-23099?

CVE-2026-23099 is a high-severity memory corruption vulnerability in Linux kernel, published on 4 Feb 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

bonding: limit BOND_MODE_8023AD to Ethernet devices

BOND_MODE_8023AD makes sense for ARPHRD_ETHER only.

syzbot reported:

BUG: KASAN: global-out-of-bounds in __hw_addr_create net/core/dev_addr_lists.c:63 [inline] BUG: KASAN: global-out-of-bounds in __hw_addr_add_ex+0x25d/0x760 net/core/dev_addr_lists.c:118 Read of size 16 at addr ffffffff8bf94040 by task syz.1.3580/19497

CPU: 1 UID: 0 PID: 19497 Comm: syz.1.3580 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: <TASK> dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:200 __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105 __hw_addr_create net/core/dev_addr_lists.c:63 [inline] __hw_addr_add_ex+0x25d/0x760 net/core/dev_addr_lists.c:118 __dev_mc_add net/core/dev_addr_lists.c:868 [inline] dev_mc_add+0xa1/0x120 net/core/dev_addr_lists.c:886 bond_enslave+0x2b8b/0x3ac0 drivers/net/bonding/bond_main.c:2180 do_set_master+0x533/0x6d0 net/core/rtnetlink.c:2963 do_setlink+0xcf0/0x41c0 net/core/rtnetlink.c:3165 rtnl_changelink net/core/rtnetlink.c:3776 [inline] __rtnl_newlink net/core/rtnetlink.c:3935 [inline] rtnl_newlink+0x161c/0x1c90 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6958 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x505/0x820 net/socket.c:2592 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2646 __sys_sendmsg+0x164/0x220 net/socket.c:2678 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x1dc/0x560 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e </TASK>

The buggy address belongs to the variable: lacpdu_mcast_addr+0x0/0x40

Weakness: CWE-125

Which versions are affected by CVE-2026-23099?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-23099?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-23099 being exploited?

There is no known exploitation of CVE-2026-23099 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-77322, BELL-CVE-2026-23099, DEBIAN-CVE-2026-23099, GHSA-cmv7-4284-j9gc, ROOT-OS-DEBIAN-11-CVE-2026-23099, ROOT-OS-DEBIAN-12-CVE-2026-23099 and 4 more.